For years, reliable voice communication services have been provided over circuit-switched networks such as the public switched telephone network (“PSTN”). More recently, packet-switched networks (e.g., the Internet) capable of carrying broadband and voice communications have been developed. Such networks allow Internet Protocol (“IP”) enabled devices to send and receive IP-based communications between one another over packet-switched networks such as the Internet. In order to bridge communications between the Internet and the PSTN, telecommunication providers deploy gateway routers (GWRs) at central offices where access to both the Internet and the PSTN are available through an IP core network. With such gateways in place, telecommunication companies are able to seamlessly switch between packet-switched and circuit-switched networks.
In recent years, telecommunication companies have sought to further improve communication services by launching initiatives to replace traditional “copper wire” transmission systems with fiber optics. In some instances, fiber optic services, such as “Fiber to the Premise,” “Fiber to the Curb,” “Fiber to the Node,” and other fiber optic access network systems (referred to collectively as “FTTx” systems), are provided to end user locations and can be connected to the PSTN.
In an exemplary FTTx network, the GWR is communicatively coupled to an optical line terminal (OLT) at the central office and serves as an interface between the IP core and the FTTx network. The OLT provides a single optical fiber to an optical splitter that divides the downstream optical signal into multiple, identical signals that are broadcast to an optical network terminal (ONT), which terminates the optical circuit at a physical location associated with an end user. The ONT serves as an interface between the optical fiber and the copper-based wire inside the premise. In a full convergence FTTx network, a single fiber optic loop is capable of supporting all packet-based services, including voice and broadband access. In known configurations, a single GWR is responsible for routing both voice and broadband communications to subscribers connected to a particular OLT. Consequently, the failure of a GWR can result in thousands of subscribers being without any voice or broadband service, including the ability to seek emergency services (e.g., dial “911”).
Accordingly, there is a need for a redundant design capability in an FTTx network that enables a customer to place voice calls, and in particular an emergency services call, after a GWR has failed or been compromised.